Your chair or stool DOES NOT work on raising or lowering height any more after you have used it for years? You are tired of a poor quality gas cylinder which is sinking or leaking but the rest parts of the chair is still good? Please consider to replace the chair lifting mechanism instead of purchasing a new whole chair.Kaleurrier gas lift cylinder is your great choice to avoid pain by SAVING MONEY! Kaleurrier gas lift cylinder is high quality,sturdy and durable,gas pressure stable,in UNIVERSAL Standard size which fits most office chairs,office,facial,salon & spa stools,etc.Its stroke fits users of varying heights. Specification: *Outer steel:2" diameter for body,1.57" for bottom.Fits 2" diameter centre hole base *Inner shaft:1.1" diameter.Fits 1.1" seat plate hole(control Mechanism) *Minimum length:9.5 inches *Maximum length when fully extended:13.5 inches *Stroke(adjustable height range): 4 inches QUESTIONS: ANSWERS: 1.How to choose a suitable gas lift cylinder? Firstly,quality is very important for pneumatic products.Kaleurrier gas lift cylinder has been passed official SGS tests and certification,meet ANSI/BIFMA X5.1 & EN 1335 General-Purpose Office Chairs standard,used high quality materials,to make sure it works smoothly,be safe during use,explosion-proof. Secondly,Our gas lift fits most office chairs, task chairs, executive chairs & stools.But it is important to measure dimensions before you purchase it,to make sure that you get the right replacement. 2.How to replace the damaged gas lift with a new one ? Please refer to the tips on the photo or search a video in Youtube. 3.If the cylinder does not fit my chair or stool,or does not work, what should I do?Or have more questions? Please contact with us - click "contact seller" first.We will give you a proper solution in 12 hours.